Casting metals.



S. P. WETHERILL, Jn.

l CASTING METALS.

APPLICATION FILED JAN. 27. 1908. nENEwED Nov. 29. 1910.

1,150,318. Panted Aug.I 17, 1915.

5 SHEETS-SHEET l.

INVENTOR;A

WITNESsl-is:

Y ATTORNEY. 'I

S. P. WETHERILL, In.

CASTING METALS.

APPLICATION FILED .IAN- 27| 1908- RENEWED NOV. 29, 19I0.

Patented Aug. 17, 1915.

5 SHEETS-SHEET 2.

A /l L L w I co i I Ill. i I l n mi@ 1T "Q y |I| il; l I() N r r l. I a)i EI WITNESSIS:

S. P. WETHEHILL, Jn.

CASTING METALS.l APPLlcATloN FILED JAN. 27. 1908. RENEwED Nov. 29. 1910.1,150,318.

.Patented Aug. 17, 1915.

s SHEETS-SHEET 3.

s. P. wEIHERIL-L, In.

` CASTING METALS.

APPLICATION FILED IAII. 27, 190s. .IIEIIIzwED Nov. :29, I9Io.

1,150,31 Patented. Aug. 17, 1915.

5 SHEETS-SHEET 4- INVENTUR Ww. L

. ATTOR WITNESSES:

S. P-WETHERILL, In. CASTING METALS.

.APPLlc-Alon FILED 1AN.21,;1908. RENEwEn Nov. 29. 19m.

1,150,318.. Patented Aug. 17, 1915.

. 5 SHEETS-SHEET 5.

E@ VIATE@ FAT I ernten.

WETHERILL FINISHED CASTINGS COMPANY,

A CORPORATION. 0F PENNSYLVANIA.

0F PHILADELPHIA, PENNSYLVANIA,

CASTING METALS.

Specilication of Letters Patent.

Patented Ang. t7, 1915.

Application led January 27, 1908, Serial No. 412,782. Renewed November29, 1910. Serial No. 594,769.

To all whomjtmay concern Be it known that I, SAMUEL PRICE WETH- ERILL,Jr., a. citizen of the United States, residingatPhiladelphia, in thecounty of Philadelphia and State have invented certain new and usefulImprovements in Casting Metals; and I do hereby declare the following tobe a full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same. v

' My invention relates to certain new and useful improvements in metalcasting furnaces and is particularly designed to provide a furnaceapplicable not only to the casting of metals of relatively lowfusibility such, for instance, as tin, lead, zinc and their alloys, butparticularly to the casting of metals of relatively high .meltingpoints, such as aluminum, brass and the like.

In carrying out the invention, I provide an internally heated pressurechamber within which the metal to be cast is contained, which metal .iskept at the high temperature necessary forcasting, by means of the heatsupplied to the interior of the chamber.A In some instances, the meltingpot or container for the metal to be cast, constitutes the lining of thefurnace chamber, and, in other instances, the melting pot or containeris a separate crucible located freely within the interior of thechamber, in such manner as to be exposed both within and without to thepressure prevailing therein. By means of this latter expedient thepressure of the aeriform fluid upon the interior walls of the containeror inner Crucible is counterbalanced by the pressure exerted upon itsexterior Walls, thereby correspondingly relieving ,f

it of unequal strains.

The pressure supplied to the interior of the chamber is derived from anysource of compressed air or similar aeriform fluid under pressure, thefunction of the compressed air or its equivalent being to exert apressure Within the chamber sufiicient to force the metal from themelting pot or cru- -cible into the casting mold, through theintermediacy of a casting mold nozzle, communicatingwith the gate of themold and extending below the surface of the molten metal.

of Pennsylvania,

An important feature of the invention consists l1n maintaining thecasting mold nozzle in such relation to the heating chamber that,lduring the intervals between successive castings, it will be constantlysub- ]ected to the heating effects of the furnace, thereby maintainingit at such a high heat that there will be no opportunity for the metalto chill within-it when the casting mold is removed, and so that, afterthe removal of the casting mold, the metal in the said castingmoldnozzle will drop freely back, regaining the level of the metal withinthe melting pot or crucible. To this end, in the preferredconstructions, the casting mold nozzle is suspended from the roof orcover' VofA the heating furnace chamber and the products of combustionfrom the furnace pass out through exit passages surrounding the upperpart of the depending nozzle.

A. further feature of the invention consists in-preventing theinfiltration of the aeriform fluid into the nozzle, or past the nozzleinto the gate of the mold during the casting operation, by interposingin the path of possible infiltration a. groove or chamber connected to asuitable vacuum, so that should the aeriform iiuid tend to gain accessto the interior of the nozzle, or to the gate ofV the mold, it will beintercepted by the vacuum groove or chamber and will be diverted fromentering the interior of the nozzle or mold.

Other features of the invention are also illustrated in the accompanyingdrawings, which show typical forms of apparatus embodying theimprovements, and these details of construction and arrangement will behereinafter more fully described.

In the drawings, Figure 1 represents, partly in section and partly inelevation, one form or modification of a metal casting furnace,assembled and arranged for carrying the invention into effect; Fig. 2represents an exterior view of the lower portion of a mold appropriatefor use therewith; Fig. 3 represents a partial top plan view of thecover of the furnace with the casting mold nozzle in place; Fig. 4represents a central longitudinal sectionand partial elevation ofanother form or modification of the invention; Figs. 5 and 6 representdetail sectional views of certain parts thereof on a somewhat largerscale than Fig. 4; Iiig.` 7 'represents a` central section and partialelevation of another form or modiicaton of the invention; and Fig. 8represents a horizontal section thereof on the plane indicated by theline 8-8 of Fig. 7. l Similar letters of reference indicate simi larparts throughout the several views.

Referring first to the construction shown in Figs. l, 2 and 3, Aindicates any suitable support for the main body portion of the.furnace, Which may conveniently consist of an outer shell B and cover Cof metal, and an inner refractory lining a of fire-clay, or thelike. Thefurnace structure is strongly braced and luted, in such manner as to.Withstand the pressure exerted Within it by the compressed air er otheraeriform fluid employed in the casting operation and also to lpreventimportant leakages of said yfiuid into the outer air or the.infiltrationof air from without; its interior, therefore, constituting an air-tightpressure chamber during the casting operation.

In the furnace shown in Figs. 1, 2 and 3, referred to, the metal to becast is intended to be contained Within a separate 4retainer or crucibleb, which retainer preferably conslsts of an ordinary commercial cruclbleof the usual graphite construction or of some other refractory materialof a character which Willnot injuriously affect the particular metal tobe cast. The retainer or crucible may be conveniently mounted uponsuitable supports, as shown,'and may be heated in any suitable manner,as, for instance, by the circular burner D supplied With a miX- ture ofgas andair fromthe blower-pipe E and gas-pipe F, as is usual ingas-heated crucible furnaces. The gas pipe F is provided with a cut-offd, the blower-pipe E is provided with a cut-ofi' cand a check valve f,and the mixer pipe G leading tothe burner is provided with a cut-olf g,'so that the quantity of air and gas appropriate to theparticularrequirements of the burner Vmay be proportioned as desired, and so thatthe supply of fuel through the mixerpipe may be cut off during thecasting operation. Compressed air or other aeriform fluid, underpressure, may be 'admitted tothe furnace chamber from a pipe H in anysuitable man.- ner. At a suitable point in the pipe H mg bellocated arelief pipe I and the pipes and I may be provided, at their junctionwith a three-way cock lc, so arranged and disposed that by turning thehandle of the cock, the pipe H may be put in communication with theinterior of the furnace chamber to admit the pressure thereto, While, atthe same time, the relief pipe I is cut off, or by other manipulationsof the said handle the pipe H may be cut off and the relie pipe I put incommunication with theinterior of the chamber, `or lastly, (as shownvvinterior of Ythe chamber.

-The casting nozzle employed in connection With the invention may be ofvarying l forms and constructions. In the form illus, -trated in Figs. land 3', the nozzle is provided With a screw-threaded top portion Zhaving adepending tubular projection m,

and likewise having a series of openings or passages s, forthe exit ofthe products of combustion from the furnace, as will hereinafter morefully appear. The depending tubular projection m and the openings orpassages s are lined Witha refractory coat-l ing n to protect them fromthe high temperatures to Which they are subjected, and this coating inmost instances, will consist of a graphite composition of the usual kindemployed for the makingof graphite crucibles. The nozzle, as thusconstructed, may be screwed into a corresponding screwthreaded apertureof the coverV -C of the furnace, and, although removable for purposes-of'repair or substitution, is intended to remain permanently in placeand depending from the cover, during the operation of the furnace, sothat the products of combustion, when the burner is in operation, willpass out through the openings or passages s, thereby keepingthe nozzleat such a high setting of the metal therein;

T indicates one portion of any suitable- I two-part, or separable mold,and t indicates the gate of the mold. The interior of the mold, as forinstance e', is connected by suitable channels as shown, With a Ipassagew leading to the vacuum pipe M, Whose function is to Withdrawl the airfrom thenold prior to each casting operation. Any suitable 4means forconnecting the interior vof the mold with the vacuum pipe during thecasting operation may be employed; for instance, a suitable cross-head Nmay be used, running in -suitable guides in the guide frame P andcapable of being raised by l meansof a screw-threaded pipe section Rconnecting with the vacuum pipeM and forming a continuation thereof, andby means of the operating lever S, or by any mechanical equivalent forthe said screvv threaded pipe and lever- The mold T makes a tight jointWith the i cover, and, 'in order to make the-joint the more effective, Iprovide the mold With an operating handle .fr and screw-threadl the moldat y, as shown in Fig. 2, so as to fit a corresponding screw-threadedrecess in the cover C. I furthermore provide it With a depending tubularprojection .e and With a conical portion c immediately above saidtubular projection, which conical portion is provided With an annulargroove p (see Fig. 2). The groove p communicates with the rase,

vacuum channel w by means of a continua tion w of that channel, asillustrated in Fig. 1, so that during the casting operation the groovewill likewise be under vacuum. rlhe purpose of this vacuum groove p isto intercept any possible inltration of compressed air that mightotherwise tendl to force its way from the interior of the furnace,during the casting operation, into the interior of the nozzle, andwhich, if not thus interrupted, would enter the metal as it rises in themold and cause blow-holes therein. The operation of this form of furnaceand its accessories will be apparent from the foregoing description;when the casting mold is not in place, the burner D will be in operationand will heat the metal in the re-v tainer or crucible and the productsof combustion will pass out through the apertures or passages c, therebykeeping the nozzle at a high heat. l/Vhen it is desired to cast, thecut-og g will be closed, thereby shutting olf the supply of fuel'to theburner, and, the three-way cock 7c will be so manipulated as .to closethe relief pipe l and to open the pressure pipe H, thereby putting thepressure pipe H into communication with the interior of the furnacechamber. immedisecured air-tight in position, and the vacuum lpipe Mthereupon withdraws the air from the mold and puts the groovepundervacuum. rllhe compressed air or its equivalent enters the furnacechamber and exerting its force upon the top of the molten metal in theretainer or crucible forces the metal into the mold and makes thedesired casting. As soon` as the casting is made, the three- Way cock 7cis manipulated in such manner as to shut olf the supply of compressedair through the pipe H, and to put the interior of the furnace chamberinto communication with the relief pipe I leading to the open air,whereupon the mold is quickly removed and disassembled, so as to releasethe casting and prevent it from chilling.

lIn the form of furnace shown in Figs. 4, 5 and G, the same generalarrangement of pressure chamber, interior Crucible, casting mold nozzleand the like, is presented as in Figs. l, 2 and 3. 1n this case,however, the crucible b may be raised, should occasion s0 require, bymeans of the vertically adjustable block b3 resting in the cup bt whosestem b5 is adapted to be raised byl means of the foot lever V, suitablycounterweighted at b, to partially relieve the operator of the weight ofthe Crucible and its contents.

- The crucible may be heated by any suitable numberof gas and airburners, as, for instance, by the side burners D', and the basal burnerD2 supplied with the necessary combustible mixture through the pipes G',which may all proceed from the same source. The metallic shell B of thefurnace chamber is,Y as before, lined with refractory material a, andmay likewise be insulated against heat radiation by suitable exteriorlagging, as shown.

rlhe furnace chamber cover C is cored out, so as to form passages s,round aboutthe upper end of the depending castingrnold nozzle m, andthese passages coinmunicate by the outlet s2, with a device forimparting the heat of the outgoing products of combustion to theincoming air, and which will presently be described. lThe casting moldnozzle m is preferably of graphite crueible composition or of likerefractory material. 1t is preferably of double conical configuration atits upper end, one of the conical surfaces fitting within the screw rin@mi' and the other conical surface fitting within a corresponding conicalrecess of the cover C with intervening refractory packing m; so that, byscrewing the ring mL into its socket, a tight oint will be insured forthe nozzle at both of its said conical surfaces. u,

rlhc passage s2 communicates with the flattened interior of the metallicheat radiator `W contained in the chamber 1V and is surrounded withsuitable refractory heat absorbing and retaining asbestos or the likeThe radiator WT leads to the exit pipe or flue Vim which conducts theproducts of combustion to the outer air, when the spring seated valve eis open. The incoming coinpressed air, entering through the air intakez2, passes through the perforated header e, refractory material fc',header et, and passages 82 and s', into the interior of the furnacechamber when the air-intake valve .e5 in the pressure pipe is opened.The si1nultaneous opening and closing of the valves e and .e5 may beeffected by any suitable mechanism, as, for instance, the operatinghandle, counterweight, rotary cam, and moderating dash-pot shown in Fig.4. The 'mode of operation of the furnace shown in Figs. Ll, 5 and 6 willbe understood from the description of the operation of the furnace shownin Figs. 1, 2 and 3. When the gas burners are ignited, the pressurevalve 25 is closed and the gas outlet valve e -is opened; so that theproducts of combustion, on their way out, keep the nozzle hot and storetheir heat in the refractory filling of the chamber `W. l/Vhen Fthe moldis in place, with its gate in alinement with the hollow interior of thenozzle the pressure valve .e5 is opened, the gas outlet valve e isclosed, and the several gas-burners are cut olf; thereby permitting thepressure to enter the chamber and effect the casting.

1n the form of furnace illustrated in Figs. 7 and 8, instead ofemploying a melting pot or crucible exposed both interiorly andexterierly to the pressure of the aeriform fluid, 1 employ as suchmelting pot or crucible the ilo refractorylining a2 of the furnacechamber B2. In this modification of the invention, moreover, the mixtureof air and gas, admitted through the ai'r tube F and gas tube G', issupplied preferably to downwardly directed twyers a3, a4, and in suchmanner tering the passage s4 pass out into the gas exit pipe H. Thecasting mold nozzle fm?, of graphite composition, or like refractorymaterial, has a main body portion of general conical outlines orconfiguration which fits within a correspondingconical aperture of thecover C? knf thefurnace. AIt is likewise conical on itsupper surface m3,and is bolted down into tight union with its metallic socket, by meansof the cap r having -a screw-threaded tubular` projection r2, upon whichis designed to be screwed the mold, as indicated in Fig. 7 by the letterT', so that the gate of the mold is in alinement with the conicalinterior of the casting mold nozzle. The gas outlet pipe H is providedwith a cut-off valve L, the gas inlet pipe G is provided with a cut-offvalve g', the air inlet pipe F is provided with a cut-off valve f andthe pressure inlet pipe L is provided with a cutofil valve Z, and theseyseveral valves or cut-offs are connected by the system of operatinglevers shown, in suchmanner that by throwing the counter-weighted levervf to one limit of its movement, the air and gas pipes of the gasburners and the gas outlet pipe will be opened and the pressure pipeclosed; whereas, Vwhen thrown to the opposite limit of its movement, thepressure pipe will be opened and the other pipes closed. By means ofthe.slots shown in the vertical member @2 of this system of levers,

the valve z/ will close after the .valves g and f', the valve g closingfirst. In the adjust,

ment indicated in Fig. 7, the pressure pipe afalve Z is assumed to beclosed, and in order r to open it and close the other. valves, f', g-

the molten metal is maintained by means of the burner flames, whoseproducts of combustion, in leaving the` furnace chamber, keep thecasting mold nozzle at such a high temperature that it is impossible forany of the casting metal to chill in said nozzle when the casting moldisfremoved. -In this respect, the construction shown in Figs. 7

and 8 shares the advantage of the like constructions shown in the otherfigures, and, at the same time, the furnace of.F1 gs. and 8 effects itscasting operations and its intermanner as vthat of the said furnaces.

Having thus described my invention, what I claim is l. A pneumaticcasting apparatus, comprising a chamber within which the molten mediate`heatings in substantially the same prising a chamber within which themolten metal to be cast is contained, a fuel-burner opening into saidchamber for heating the same by internal combustion, a casting-moldnozzle communicating with the molten metal, a conduit for supplyingcompressed airto the chamber during the casting operations, and meansfor opening the chamber for the escape of the products of combustionduring the interval between the casting operations and for closing itduring the casting operations, the said casting-mold nozzle being in thepath ofthe outgoing products of combustion; substantially as described;

3. A pneumatic casting apparatus, comprising a pressure chamber'forcontaining ,Y

\ the casting-metal, means for internally heating said chamber, acasting-mold lnozzle -dipping from above into the casting-metal,

and means for producing within said chamber, a super-atmosphericpressure; substantially as described. Y

4. A pneumatic casting apparatus, comprising an internally-heatedpressure chamber, a casting-metal container located therein and exposedinteriorly to the pressurel pre-l vailing in the chamber, means fortaking up and counter-balancing the tendency of said interior pressureto rupture the walls of the casting-metal container, and a casting mold-nozzle dipping from aboveinto the castingmetal`; substantially asdescribed.

5. A pneumatic casting apparatus, provided with an air-pressure chamberwithin which the metal to be cast is contained, a I

` casting mold and a casting-mold nozzle, and

means for intercepting the infiltration of the compressed air from thepressure chamber into the mold; substantially as described.

6. A pneumatic casting apparatus, provided with an air-pressure chamberwithin which the metal to be cast is contained, a

casting-mold and a casting-mold nozzle, and means for intercepting theinfiltration of the compressed'air from the pressure chamber into themold, said means consisting of an exhaust connection interposed `in the,path of possible infiltration; substantially as described.

7. A pneumatic casting apparatus, pro-I vided With a combined furnaceand pressure chamber, a casting mold, and a depending casting-moldnozzle having at its point of suspension outlying passages for thepassage ofthe products of combustion fromrthe chamber; substantially asdescribed.

8. A pneumatic casting apparatus, comprising an internally heatedpressure chamber, Within which the molten metal to be cast is contained,a casting mold communieating with thev molten meta-l therein, and valvemechanism for simultanenously opening the pressure admission and closingthe relief. exhaust of said chamber; substantially as described.

In testimony whereof I ax my signature,

in presence of two Witnesses.

SAMUEL PRICE WETHERILL, JB. Witnesses: v

' F. J: KING, A

T. HoPrLE.

